The petrochemical pesticides disrupt the protein synthesis in the plants, which weakens them and makes them call out for more bugs. You may be interested in the work of Francis Chaboussou and the trophobiosis concepts.
It's not so much the pesticides (insecticides, fungicides etc), but specifically the petroleum based and phosphate based fertilizers that are deterimental to the beneficial bacteria in the soil. These bacteria do everything from fixing nitrogen from the atmosphere, to breaking down organic matter, and mineralization, or releasing nutrients for plants to consume. They also out number the bad pathogens and out compete them for space on root systems and leaves. Without their presence, the plants are like drug addicts waiting for a fix. The key here is to focus our efforts on feeding the soil and the soil will feed the plants!
I always thought or at least my "pests", like nice beautiful lush new healthy foiliage. they don't like the blackspotted, mildewed, yellow disfigured leaves. and would certainly skip a weak plant. That's called, the bugs are smarter than we are concept. BSTWA.
as far as petro based anything, i've always heard diesel is a weedkiller the first year and a fertilizer after that. hmmm. that's probably why they test for microbes in the fuel cause it can clog your filter.
I'm beginning to think there will never be just an observational, totally neutral study.
it's about whatever sells something whether it be a pesticide, herbacide, organic magazine or whatever. i'm very curious about how everything inter-relates, out of my own curiosity, and i think i'll just have to rely on my own observations for now.
hello wrightie, I think that's what makes gardening so fun. Plants are just so unpredictable at times and when the experts list all of the possible exceptions to their rules and theories, it makes you wonder what they really had to say in the first place or if the book is worth the ink and paper it's printed on.